First time I saw Skreech, I, too, thought it was a robot chicken of sorts, and I only knew of his existence as the portrait appeared while configuring the names. It was a character I had never found in the game. I started going back through it and I looked up how to unlock Skreech. There's no way I would know to go back and stand in that very specific spot after talking to him and his mother if I didn't try to rename everyone and look up the secret online (in my original playthrough, easily accessible internet wasn't even a thing yet).